81027800 has 96 divisors (see below), whose sum is σ = 222366720. Its totient is φ = 26870400.

The previous prime is 81027787. The next prime is 81027809. The reversal of 81027800 is 872018.

It is a self number, because there is not a number n which added to its sum of digits gives 81027800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81027809) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 42467 + ... + 44333.

It is an arithmetic number, because the mean of its divisors is an integer number (2316320).

Almost surely, 2^81027800 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81027800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111183360).

81027800 is an abundant number, since it is smaller than the sum of its proper divisors (141338920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81027800 is a wasteful number, since it uses less digits than its factorization.

81027800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1921 (or 1912 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 26.

The square root of 81027800 is about 9001.5443119500. The cubic root of 81027800 is about 432.7243648601.

Adding to 81027800 its reverse (872018), we get a palindrome (81899818).

The spelling of 81027800 in words is "eighty-one million, twenty-seven thousand, eight hundred".